Mining operations involving coal, iron ore, copper, and/or other materials include dangerous activities. These operations require miners to enter subterranean mines and perform various arduous mining activities. Such subterranean mines have limited oxygen due to their isolation from earth's outside atmosphere. Accordingly, one risk involved with such operations includes the potential for fires within the mine. Even a small fire can consume the limited oxygen supply within the mine and emit enough smoke to seriously harm the miners within the mine whom may not be able to exit the mine fast enough.
One known means for alleviating such a risk includes the provision of Self-Contained Self-Rescuer (SCSR) devices within the mine. Common SCSR's include closed-loop breathing apparatus comprising a mask, a mouthpiece, and/or a nose-piece, an inlet fluidly coupled to a container containing a small amount of breathable air, i.e., oxygen, and an outlet coupled to a carbon dioxide scrubber. When donned by a miner, such known SCSR's may provide the miner with breathable air for a fixed time period, thereby allowing the miner to safely exit the mine to minimize risk of suffocation due to smoke inhalation or lack of oxygen.
One concern arising with the use of SCSR's is that miners are not familiar with how the SCSR operates. More particularly, miners may not know what to expect when donning and breathing with the SCSR. For example, as mentioned, typical SCSR's include closed-loop systems comprising a breathing apparatus coupled to both a supply of breathable air and a carbon dioxide scrubbing device. The carbon dioxide scrubbing device tends to increase the temperature of the recycled breathable air. Therefore, during use, the sensation felt by the user may include a rise in the temperature of the breathable air, as well as resistance to the normal flow of breath. It is conceivable, for example, that a user who is not familiar with the SCSR may think that these sensations mean that the SCSR is malfunctioning. Alternatively, these sensations may cause a user to be frightened and panic. In either situation, the user may be tempted to remove and discard the SCSR, thereby placing him or herself in danger.
Accordingly, an important aspect of providing SCSR's within mines includes training miners and other mine personnel on the proper operation and utilization of the SCSR's. The Mine Safety and Health Administration (MSHA) requires that each miner undergo annual expectation training. However, it may not be cost-effective to perform such training with the actual commercialized SCSR devices that are provided in the mines. Therefore, the training allows for each miner to undergo annual training that includes breathing through a realistic Self-Contained Self-Rescuer (SCSR) “training unit” that simulates the sensation of the breathing resistance and heat generated by an actual SCSR.